Displacement Measurements for Cyclic Triaxial Tests Using Digital Image Correlation
E. Montemayor, Richard Ray · 2005
Digital imaging and the Vic-3D program were used to measure deformations during a displacement-controlled cyclic triaxial test of a clay specimen confined by vacuum. Seven stages of testing, each of 50 cycles, were completed. Measurements from an LVDT and the Vic-3D image correlation program were compared using two methods: 1) A direct comparison of strains with estimated error bands and 2) A statistical test of coincidence of resilient modulus regression curves using a dummy variable model and an F-test. The Vic-3D program successfully replicated LVDT results. Both total and plastic strains exhibited similar trends and magnitudes. Resilient modulus curves were statistically coincident at the 99% confidence level.